The steady, laminar boundary-layer flow of an incompressible Eyring-Powell fluid is studied numerically over a horizontal flat permeable plate. A convective surface boundary condition is taken into consideration to define thermal boundary condition. The boundary-layer flow equations are reduced into the system of nonlinear, coupled, nondimensional ordinary differential equations by employing the suitable similarity transformation. This system is then solved by applying the Galerkin finite element method. The influence of the Biot number, Prandtl number, Eyring-Powell fluid parameters, and suction/injection parameter on the velocity and temperature profiles is shown graphically. The impact of physical parameters on the rate of heat transfer is shown graphically and in tabulated form. The excellent validation of the present numerical results is achieved. This study will have an important application in bearing in mechanical components for reducing the friction and cooling in rockets and jet.

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PurposeIn the present computational study, the heat transfer and two-dimensional natural convection flow of non-Newtonian power-law fluid in a tilted rectangular enclosure is examined. The left wall of enclosure is subjected to spatially varying sinusoidal temperature distribution and right wall is cooled isothermally while the upper and lower walls are retained to be adiabatic. The flow is considered to be laminar, steady and incompressible under the influence of magnetic field. The governing mass, momentum and energy equations are transformed into dimensionless form in terms of stream function, vorticity and temperature.Design/methodology/approachThen resulted highly non-linear partial differential equations are solved computationally using Galerkin finite element method.FindingsThe exhaustive flow pattern and temperature fields are displayed through streamlines and isotherm contours for various parameters, namely, Prandtl number, Rayleigh number, Hartmann number by considering different power-law index and inclination angle. The effect of inclination angle on average Nusselt number is also shown graphically. This problem observes the potential vortex flow with elliptical core. The results show that the circular strength of the vortex formed reduces as the magnetic field strength grows. As the inclination angle increases the intensity of flow field decreases while the value of average Nusselt number increases.Originality/valueThis study has important applications in thermal management such as cooling techniques used in buildings, nuclear reactors, heat exchangers and power generators.

Purpose -The purpose of this paper is to deal with the study of free convection magnetohydrodynamic (MHD) boundary layer flow of an incompressible viscoelastic fluid along an inclined moving plate and heat transfer characteristics with prescribed quadratic power-law surface temperature. Design/methodology/approach -The governing partial differential equations are transformed into non-dimensional, non-linear coupled ordinary differential equations which are solved numerically by robust Galerkin finite element method. Findings -Numerical results for the dimensionless velocity and temperature profiles are displayed graphically for various physical parameters such as viscoelasticity, Prandtl number, angle of inclination parameter, magnetic and buoyancy parameter. The local Nusselt number is found to be the decreasing function of magnetic field parameter whereas it increases with increasing values of Prandtl number, viscoelastic parameter and buoyancy parameter. Practical implications -The present problem finds significant applications in MHD power generators, cooling of nuclear reactors, thin film solar energy collector devices. Originality/value -The objective of this work is to analyze the heat transfer of convective MHD viscoelastic fluid along a moving inclined plate with quadratic power law surface temperature. An extensively validated, highly efficient, variation finite element code is used to study this problem. The results are validated and demonstrated graphically.

The heat and mass transfer in an unsteady boundary layer flow of an incompressible, laminar, natural convective third-grade fluid is studied. The flow is taken over a semi-infinite vertical porous plate with the temperature-dependent fluid properties by taking into account the effect of viscous dissipation and variable suction. The partial differential equations governing the problem are reduced into the nonlinear, coupled, nondimensional ordinary differential equations with the help of suitable similarity transformations. The Galerkin Finite Element Method is implemented to solve this acquired system. The effects of various significant parameters such as Grashof number, Prandtl number, Eckert number, Solutal Grashof number and Schmidt number on dimensionless velocity, temperature and concentration profiles are presented graphically. The Nusselt number is found to be depressed whereas the Sherwood number is observed to be enhanced with the increasing values of Grashof number and Prandtl number. The study has important applications in chemical process industries such as filtration in food industry, production of drinking water and recovering salts from solutions.